Sccott, it is clear what you are talking about.
Programmers may prefer to change the information for different users. I have
argued that in attempting to provide different people with the same
information that is a bad appraoch to information management.
Servers have nothing to do with CSS, and the andling does not change.
Web designers need to know how web standards are imlemented. CSS and HTML are
in the same bag hereBut using CSS provides for sound underlying semantics
(that you keep asking for and then claim aren't there) while using remodelled
HTML obscures those semantics.
Changing the types of content requires reprogramming ofd a customised
presentation whether it is done in HTML, XML, CSS, RTF, or anything else, and
then generated. THe point is that it is not relevant (incidentally it isn't
relevant whether the content is dynamic or not - the principles apply
anyway).
The case where users are customising for themselves is a different kettle of
fish, The work trhat Dan Brickley has done is a good place to investigate the
state of the art here. But even that begins from a common basis with the same
starting point being there for all to return to. There is an important
difference between customised information (I read the sprots section and you
read the business section of the newspaper) and customised presentation (I
get the broadsheet and spread it out on the table, you browse it
electronically with a palm pilot). This discussion is only relevant to the
latter case, obviously.
Charles McCN
On Wed, 19 Jan 2000, Scott Luebking wrote:
Hi, Charles
I may not have been making myself very clear. The situation I'm talking
about is where web pages are being generated dynamically, e.g. results
from search engines, personalized web pages, etc. The contents of the
web pages will vary from user to user. This means that a goal
of each user getting the same content is probably in conflict with
why web pages are being generated dynamically.
I believe that your analysis of style sheets is not taking in consideration
the programmers who will do the programming of the software which will
be creating the web pages. How will the approach you are proposing
of using style sheets make their work easier?
First, style sheets require that the web pages be written with enough
information for classes, etc, to be able to be used in different formats.
Why would the programmer not prefer just to have the software just
write out different formats instead of doing all the works of classes, etc?
The second problem for programmers is what to do if new content requires
new forms. That means that new classes have to be developed. The
style sheets have to be changed. There can be version skews with
style sheets. The style sheets have to be tested with each browser.
Sounds like a lot of extra work with minimal benefit.
I don't see a lot of benefit to server-side style sheets for dynamically
generated web pages. You have to figure out the server's implementation
of style sheets, etc. What happens if a new type of server is brought in?
The style sheet handling can break. Again, what is the advantage
to the programmer?
Each fall I help with teaching the New Product Development course in
Berkeley's business school. One of the principles I strongly recommend
is "user empathy". Students often come in with what they believe
to be the correct technological solution to something and have
a hard time not understanding why users would not want the
technological solution. I tell them that they need to step out
of who they are and into the shoes of various types of users
and also the people who are developing or maintaining the technology.
The ability to empathize with the various people who will be
involved with the technology gives better insight into when the
technology may or may not be useful.
Scott
> So we get down to the question of what is the best solution to provide.
>
> It is clear that users are happy to have a presentation that suits their
> needs. It is equally clear that they are concerned about having something
> whose semantic content is different from that supplied to someone else,
> simply because that is how their needs are perceived. And finally I think it
> is pretty clear that telling a user to go write their own style sheet is not
> going to be a solution for the current generation of HTML, and is not likely
> to become feasible until the so-called semantic web becomes a reality, and
> machines are able to understand more complex metadata about a page and
> relate it to what the user has said they like and dislike.
>
> Scott has suggested using dynamically generated web pages which are
> customised to suit different sets of needs. In fact there is value in this
> approach in circumstances where all else fails, but this case does not seem
> to be one of those. (For an example of one, read
> http://www.sidar.org/anima.htm - if you don't read spanish go to
> http://babelfish.altavista.com and ask it for a translation - that is not
> brilliant but makes some sense by the second read)
>
> I would suggest instead encoding the information with all the known semantics
> once, and making different stylesheets available. This is in fact why the
> HTML specification reserved the value "alternate" for the rel attribute.
> Unfortunately there are very few browsers around that fully implement HTML4 -
> the only ones I know that make the claim are Ice and I believe Opera 4 will -
> so it would be useful to provide a change-stylesheet link for people to swap
> between different styles. This will provide everyone with the assurance that
> they are getting the same content, and the semantics are all there if they
> want to look into them, while at the same time allowing for customisation.
> Further, it allows advanced users to enhance the customisation by adding
> their own stylesheet.
>
> I believe that a server-side provision of a stylesheet is likely to be less
> burden than rewirting the entire pages model, improves the separation of
> content from presentation to allow the latter to be adjusted as much as
> possible, and incidentally reinforces to the author which is which, since
> they need to determine the circumstances in which their presentation is
> actually used to convey semantics (the order of things in a table is a good
> example). It also provides all semantic information as a first-class object,
> accessible through the web, rather than hiding some of it in a database
> system that is invisible to the end user.
>
> Cheers
>
> Charles McCN
--
Charles McCathieNevile mailto:charles@w3.org phone: +61 (0) 409 134 136
W3C Web Accessibility Initiative http://www.w3.org/WAI
21 Mitchell Street, Footscray, VIC 3011, Australia